The present invention relates to a method of communicating between a motor vehicle and a diagnostic unit, whereby a wireless communication connection is established between the motor vehicle and the diagnostic unit after an authorization of the diagnostic unit has been checked. Furthermore, the present invention relates to a diagnostic unit for implementing such a method.
According to the state of the art, normally a wired interface is used for communicating between a motor vehicle and a diagnostic unit for diagnostic and/or programming purposes or for accessing customer, adaptation, and/or vehicle data. In such a case, the diagnostic, programming and data communications with the vehicle can take place only after a manual connection. Particularly in the service environment of the data exchange, this can therefore only be accomplished at selected process points.
As an alternative to wired interfaces, wireless interfaces are known for communicating between a motor vehicle and a diagnostic unit. However, depending upon the type of wireless communication, these have various disadvantages.
For example, at present, telecommunication access on a cellular basis, as a rule, is not available in the case of every motor vehicle and, in addition, causes further expenses as a result of service provider fees. Also, today's telephone interfaces are not uniform worldwide. In order to take into account all variants and local differences, considerable technical and financial expenditures would be required.
In addition, known wireless interfaces for communicating between a motor vehicle and a diagnostic unit often do not provide any manner of checking the authorization of the diagnostic unit. If a checking of an authorization of the diagnostic unit is provided, disadvantageously, additional equipment-related expenditures, program-related expenditures, and/or communication expenditures are required.
The invention provides a simple method of communicating between a motor vehicle and a diagnostic unit, whereby a wireless communication connection is established between the motor vehicle and the diagnostic unit, after an authorization of the diagnostic unit has been checked. The invention further provides for a diagnostic unit which is suitable for implementing such a method.
According to the invention, a method is provided whereby the diagnostic unit is connected with a vehicle key assigned to the motor vehicle, and the authorization of the diagnostic unit is checked by use of authorization data stored in the vehicle key.
Further according to the invention, a diagnostic system is provided which has devices for connecting with a vehicle key assigned to the motor vehicle. A diagnostic unit is suitable for receiving authorization data from the vehicle key, for indirect or direct wireless communication with the motor vehicle, and for proving an authorization with respect to the motor vehicle by way of the received authorization data.
In modern motor vehicles, electronic locking systems are increasingly used, which permit the opening and locking of a vehicle also by way of a wireless communication. For securing the communication between the vehicle key and the vehicle, as a rule, a bidirectional data exchange is carried out. For this purpose, authorization data are stored in the vehicle key for checking its authorization, for example, in order to unlock the vehicle. The invention utilizes this principle for checking an authorization to solve another task, specifically the present task.
The method according to the invention requires only minimal equipment-related and program-related expenditures, yet nevertheless permits an effective authorization check of the diagnostic unit for communicating with the motor vehicle.
According to a first preferred variant of the present invention, the diagnostic unit has its own devices for direct wireless communication with the motor vehicle, and only authorization data are transmitted from the vehicle key to the diagnostic unit.
Which communication devices on the part of the diagnostic unit are to be provided for the wireless communication with the motor vehicle is a function of the selected communication technology. Here, many different wireless technologies can be used (WLAN, Bluetooth, etc.). The diagnostic unit may, for example, have a connected WLAN router. The diagnostic unit preferably even has suitable integrated communication devices, such as an integrated WLAN interface.
In this variant of the invention, the motor vehicle also has corresponding communication devices, such as a WLAN Gateway, for most of the feasible communication technologies. As an alternative, the motor vehicle can be temporarily equipped with corresponding communication devices in a manner known per se, for example, only in the shop area. In addition, the motor vehicle should be in sufficient proximity to the communication devices of the diagnostic unit.
In a particularly preferred embodiment of the first variant of the invention, the diagnostic unit has suitable devices for communicating with the motor vehicle, also directly, by way of the same radio technology by which the vehicle key also communicates with the vehicle during locking and unlocking of the vehicle. Such an embodiment has the advantage that no additional equipment, such as a WLAN Gateway, has to be provided on the motor vehicle. Instead, the already existing communication devices of the motor vehicle for the electric locking system can be used.
The transmission of the authorization data from the vehicle key to the diagnostic unit can take place, for example, by way of a communication connection between a vehicle key reading device, in which the vehicle key is placed, and the diagnostic unit. The communication connection between the vehicle key reading device and the diagnostic unit is preferably wire-bound.
The authorization data stored in the vehicle key are processed, for example, coded, as required, for transmission to the diagnostic unit. Depending on the embodiment, in the case of the diagnostic unit, as required, another processing, such as a code translation, of the transmitted data is to be provided. By way of the received authorization data, the diagnostic unit establishes its authorization to communicate with the motor vehicle with respect to the motor vehicle. For example, a so-called session key for a coded transmission can be generated on the basis of the received authorization data.
After the successful establishment of a communication connection between the motor vehicle and the diagnostic unit, according to this variant of the invention, the vehicle key must not necessarily remain in the vehicle key reading device.
According to a second preferred variant of the present invention, communication of the diagnostic unit with the motor vehicle takes place by way of the vehicle key. The diagnostic unit, therefore, communicates indirectly with the motor vehicle. In this case, the diagnostic unit does not have to have its own devices for wirelessly communicating with the motor vehicle. According to this variant of the invention, the wireless communication connection (typically constructed as a radio interface), which is provided anyhow between the vehicle key and the vehicle, for example, for the unlocking of the motor vehicle, is utilized for the communication of the diagnostic unit with the motor vehicle.
According to this second variant of the invention, for the indirect wireless communication with the motor vehicle, the diagnostic unit is connected with a vehicle key writing/reading device, in which the vehicle key is placed. The diagnostic unit only has to be suitable for the connection of such a vehicle key writing/reading device and for the indirect communication with the motor vehicle by way of a vehicle key placed in the vehicle key writing/reading device.
In the case of the communication of this variant according to the invention, the vehicle key, together with the vehicle key writing/reading device, operates, as it were, as a gateway between the motor vehicle and the diagnostic unit. Before the establishment of the communication connection between the motor vehicle and the diagnostic unit, in a manner known per se, the authorization of the vehicle key is checked by way of the authorization data stored in this vehicle key. The authorization data do not need to be transmitted to the diagnostic unit.
For a proper functioning of a method according to this second variant of the invention, the motor vehicle has to be in sufficient proximity to the vehicle key placed in the vehicle key writing/reading device.
In addition to the above-mentioned advantages, there is the additional advantage of a communication method according to the invention wherein there are no service provider costs. The communication according to the present invention is otherwise also independent of a provider, a mobile telecommunication network, and/or other public or partially public communication networks.
In many cases, the described forms of communication can be implemented by way of currently existing technical devices and require no or low expenditures for the adaptation of the existing infrastructure.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.